What's the smarter solution for bringing mobility to 21st century cities: bus rapid transit (BRT) or light rail? With questions this big, it's important to consider all the perspectives.

A team of researchers at the World Resources Institute (WRI) recently produced a report that goes against the grain. WRI analyzed and compared BRT and light rail as two options for Maryland's Purple Line Project, a 16-mile transit corridor that will connect the D.C. suburbs. In January, the Institute came down in favor of BRT, with a statement announcing that "enhanced buses ... would cost less, offer similar services, and fight global warming better than light-rail cars."

Our main question related not to what's in the study, but rather, what seems to be left out. It's a common observation that light rail delivers benefit beyond transit alone, in the form of transit-oriented development that springs up as a result of developers, business owners and homebuyers seeking proximity to the train stations.

The team at WRI was happy to share their take on this and other issues. I interviewed the study's lead author, Greg Fuhs, and WRI's senior transport engineer Dario Hidalgo, about BRT/LRT, transit prejudices, and how other cities can apply this analysis to their own planning process.

Julia Levitt: In your study, you found that BRT outperformed light rail in cutting overall CO2 emissions. How did you come to that conclusion?

Greg Fuhs: Our study actually corroborates what is already stated in the Maryland Transit Administration’s Draft Environmental Impact Statement (DEIS): that BRT would be better on CO2 emissions for the Purple Line. This is a surprising finding to many, because it is often assumed that switching to an electric system such as light rail would reduce CO2 emissions. However, it is very important to consider the electricity source, and in our region the dominant source is currently coal-fired power plants.

So, while energy consumption from roadways would decrease with introduction of either light rail or BRT, for light rail the resulting emissions reduction is not enough to counterbalance the effect caused by the high electricity CO2 emission factor. In fact, CO2 emissions are projected to increase from business as usual with a light rail Purple Line. While this could change in the future with a major and permanent shift to low-carbon energy sources, for the foreseeable future we would likely continue to see higher CO2 emissions from light rail in this case.

JL: Critics of your report have pointed out that in North America, many people own cars, which gives them a choice that many riders overseas don't have, and that people who have the choice of driving a personal vehicle are often inclined to find light rail cars an acceptable alternative, but are less likely to ride buses. What's your take on this argument?

Dario Hidalgo: It is a common perception that a light rail system would attract more riders than BRT, and that is reflected in the demand estimations incorporated in the DEIS. However, I would raise two points:

First, in this case it is not at all certain that there would be a large enough increase in ridership to justify the significantly higher cost of light rail. For example, if we take just MTA’s ridership estimates, for the “Medium Investment” LRT and BRT alternatives we see a projection of 62,600 and 51,800 riders per day, respectively. That’s only about 20% more riders for light rail, yet the projected capital cost of the light rail system is more than twice that of BRT ($1.2 billion vs. $579 million), and also includes higher annual operation and maintenance costs.

Second, it is worth drawing a distinction between “buses” and “BRT.” The concept of bus rapid transit is not well understood in the United States, where there are only a few systems currently in operation. In reality, BRT would be designed more like a light rail than a standard bus system, with features like dedicated lanes, signal priority, pre-pay boarding, elevated station platforms, and efficient and comfortable vehicles that make it much more efficient and appealing than a traditional bus service. For the Purple Line, BRT would also offer travel times that are competitive with light rail. With a well-designed, well-operated, and well-advertised BRT in place, there is good reason to believe that many people would use and appreciate the system.

JL: Although your report shows that BRT will cost about half the amount of a light rail system, other studies show that light rail systems, because they are permanent structures, do more to encourage transit-oriented development. Was TOD a factor in the EMBARQ study? Do you think that BRT can facilitate and encourage dense development at a similar level?

GF: We did not look specifically at the TOD factor in our study. However, one cannot assume that transit-oriented development would be sparked by light rail but not BRT. For example, a recent study by the American Public Transportation Association looking at this issue considers both rail and traditional bus systems (although unfortunately it does not look at BRT specifically), and indicates that both can lead to significant positive land use changes. In any case, there is no reason to assume that LRT has a greater impact on land use than high-quality BRT if the systems provide similar travel times, capacities, and overall quality of service, as would be the case for the Purple Line. Moreover, developers can benefit from the shorter implementation time that BRT projects bring as compared to LRT.

DH: Also, regarding permanence, this is a somewhat relative concept. For example, there were thousands of miles of tram networks in the U.S. by 1940; much of this system was dismantled before 1970 with the rise of the automobile and suburbia. The forces behind development are not limited to the technology of transit vehicles, but also depend on factors such as accessibility, enabling policies, and background economics.

JL: Do you feel that the EMBARQ study comparing BRT/LRT can be easily applied to other regions and cities, or is this evaluation case-specific? What factors do you suggest other cities consider as top priorities when making their own decisions about public transportation?

GF: While certain general principles may apply to multiple locations (e.g., public transit is generally an asset to the community and its development should be encouraged), in reality every evaluation like this must be case-specific. After all, even if different locations have similar demographic and/or geographic characteristics, every local population has different needs and preferences and faces unique transportation challenges and political circumstances.

In considering public transportation projects, the first priority must be to determine if there is a need for a transit system to move people within the proposed corridor, and the entire decisionmaking process should be conducted in close consultation with the affected communities. Other important considerations include determining how much benefit a transit system could bring in terms of improved mobility, greater access to transport, incentives for economic development, and improved environmental quality. Further, and particularly in these lean economic times, the cost-effectiveness of the proposed system is a critical factor (especially in terms of competing for scarce state and federal funding). There is also evidence that urban infrastructure projects entail high risk of not meeting preliminary demand and cost estimates, and thus not realizing the projected cost-effectiveness. Such risks should be considered in the analysis and decision making process, but so far this has not been the case for the Purple Line project. Our study does attempt to quantify this risk by providing a sensitivity analysis of Purple Line cost and ridership projections, and we recommend that similar efforts be undertaken in future transit proposals.

In our study specifically, we emphasize that in this time of financial and climate crisis, cost-effectiveness, risk, and greenhouse gas emissions are especially important factors to consider. And in these three cases, BRT comes out as the better option for the Purple Line, as can be the case in other projects. Going forward, we would encourage decision makers and communities not to select a project based on perceptions, but on good analytics.

"However, it is very important to consider the electricity source, and in our region the dominant source is currently coal-fired power plants."

That's a very short-sighted statement. They started by making the assumption that the energy choices are diesels directly burning oil and transmitted electricity generated by burning coal. But neither coal nor petroleum are going to be fuels for too much longer, so in a generation, this is all going to have to be rethought.

BRT systems have never delivered on their promise, just as buses were never as frequent or pleasant to ride as the streetcars they replaced. I wonder why. Krawk!

"However, it is very important to consider the electricity source, and in our region the dominant source is currently coal-fired power plants."

That's a very short-sighted statement. They started by making the assumption that the energy choices are diesels directly burning oil and transmitted electricity generated by burning coal. But neither coal nor petroleum are going to be fuels for too much longer, so in a generation, this is all going to have to be rethought.

BRT systems have never delivered on their promise, just as buses were never as frequent or pleasant to ride as the streetcars they replaced. I wonder why. Krawk!

Julia, this is a great piece. My first reaction was to dismiss the WRI position (I do tend to agree with the previous comment about short-sightedness), but I have a lot of respect for WRI. It's surprising that they found BRT to be so much cheaper than rail, including operating and maintenance costs. That's a puzzle -- not usually the case in this country.

I'm not convinced by their arguments (esp. the fact that they did not really look into TOD), but I want to encourage you to do more of these contrarian explorations.

I too found it interesting that they found the cost to operate BRT was cheaper than LRT, unless that's because they did include the capital costs too. No transit operator in this country has found it cheaper to operate buses and even the National Transportation Database reports a country wide average of 60 cents per mile in operating costs for LRT vs. 80 cents per mile in bus operating costs per mile.

I also have to wonder if they looked at LA's BRT, and if they did just how closely they looked at it. Reason being that LA's BRT, which by the way is the only really successful BRT that I'm aware of, is now a victim of its own success.

It has reached capacity and there is no way that they can increase service on the line at present. The only alternative would be to close every street crossing, and even that only helps a little and won't be adequate in the near future.

So now LA is starting to look into how to convert the busway into LRT, something that will come at a cost of billions of dollars and most likely great inconvenience to those who ride the BRT.

Posted by: Alan B on 6 Feb 09

The problem with making the BRT/LRT energy comparison is that it is done by looking at existing systems, and no one is really optimizing their system for energy efficiency in the first place. Transit systems are designed firstly to move people and after that to save money. So if electricity is cheap, no one bothers to incur the labor cost of reconfiguring trains for off-peak hours -- you run the same long trains you run in rush hour and people just get lots of space. The thing is most of the riders on either system type are during peak hours, but most of the vehicle trips are off peak, so those mostly empty trains rolling through the night and in the middle of the day dramatically increase the energy consumption of the system relative to buses. If any LRT system were willing to spend a little extra on trains they could have bus sized single car trains to handle the off peak load at basically the same energy cost as BRT, with dramatically improved energy per passenger during rush hour, but energy efficiency has not been a primary concern of any transit system.

Throughout the nation, the use of electricity for mass transit has been caught at one time or another, especially for the Boston Mass M.B.T.A.'s Washington st. Silver line, and the The Urban Ring, in which it has been in the middle of a lively public argumentation about environment and its relation to limited energy resources. A trip to Paris France, or Moscow Russia show cases their urban ring systems to be pure electric traction, of heavy rail. I know , I've been there, and can appreciate it very much. Why can't Boston do the same? Why is it that the big dig political thugs can musle $14.5 Plus Billion dollars for a measily 7 route miles of highway through Boston Mass, while the MBTA cannot secure funding to implement phasing in an urban ring of quality heavy rail , electric traction??? I want to point this out from an electrical point of view.

The issue comes down to two questions: Should we go for the possibly greater economy and efficiency of burning fossil fuels in all kinds of buses, commuter rail, diesel powered light rail and above all the preposterous Bus Rapid Transit powered by compressed natural gas for the Urban ring , or the klunker duel mode stinking diesel/electric buses for the silver line???!! or do we have to put up with the hodgepodge design of the urban ring and learn to live and work in an environment of even higher co2 and noise pollution this causes ?--- or Should we generate electricity in power plants away from where we live and work powering our mass transit vehicles with clean electric means and there by keeping air and noise pollution away from people?

Running mass transit vehicles with diesel or even compressed natural gas and I would even address in a limited way the hydrogen fuel cell technology even though it may be emissions free, can look like an efficient technique for extracting the maximum economy from fuel.... But this does put the exhaust fumes , noise and waste heat right where people live and work exposing them to dangerous concentrations of air and noise pollutants at ground level. Reductions of these type of pollutions to safe levels by control equipment on the individual vehicles is not a realistic expectation. To legislate and regulate pollution control on thousands of those fossil fuel burning transit vehicles would be an incredibly costly solution , if not out right an impossibility given the poor track record maintenance of such transit agencies that pander to the bus manufacturing and diesel fume[sic] oil industry lobby, or in my opinion some kind of mass transit on going conspiracy since the 1930s...

If we remotely locate our generating plants that burn fossil fuels there and send clean electric energy to our population centers, we drastically reduce pollution for two reasons: First , we are keeping combustion and noise effluents away from people; and second the opportunities for pollution control on fuel burners are real and substantial. As electric utilities, some have clearly demostrated, it is readily within our technical and administrative capabilities to effect maximum pollution reduction at power plants. Of course running mass transit vehicles by electric energy remotely generated is charged with being at odds with the present emphasis on efficient use of the limited fuel supplies, regardless if they are fossil fuels or renewable type or green sources of generating electricity. Heat losses in generation and transmission and distribution losses reduce the amount of useful energy extracted from the fuel, but some power plant systems do have the advantage of being meticulously designed an maintained, whereas combustion inefficiencies due to poor design and lack of maintenance in the thousands of fossil fuel mass transit vehicles certainly accounts for very substantial HIDDEN LOSSES. Case in point, buses that have to idle in winter months in the bus storage facilities or repair. It is extremely likely that , on the basis of energy extracted from fuel, the average efficiency of fossil fueled motorized mass transit vehicles--considering design, maintenance--- is lower than the average efficiency of pure electric mass trasit systems (taking in all the wiring losses back to the generating plant) . Another case in point , a first for North American continent, as of Sept 5, 2001 , the city of Calgary , Alberta Canada, a prarie town in the middle of Canadian oil country , launched its "Ride The Wind" project. E-MAX the first company in North America to supply wind power electricity to fuel an entire light rail system. A total win- win situation by the wind system..A project that prvides 100% emmisions free C-train system and contributes significantly towards the city of Calgary's goal to reduce its corporate CO2 emissions!!!!

A critically important advantage of pure electric mass transit is the very high horsepower utilization at the rail or wheel in the case of trackless trolley, which is adjustable with the incorporation of the new type of Varible frequency drives , adjusting according to loads of people being carried, without robbing power from other vehicle functions such as heating and or air conditioning. A typical problem in fossil fueled transit vehicles that operate in summer heat. Try riding on some MBTA buses on a hot day!! Also that is another reason why we have that so called urban heat island that contributes to smog because or the stinking bus beltching not only smoke and roaring with noise, but heat as well because of that burning of fuel within the vehicle!!! No wonder why on weekends, city dwellers try to escape the city for the country. That is also why we have people living in the sprawling suburbs. that waste heat is just not healthy where people live and work.

The controversy environment and energy crisis will continue to rage on as long as we the people let companies lobby our elected officials for more highways/airports and other companys that would thwart the development of electric mass transit systems. Or in other words a silent continuation of the great mass transit conspiarcy that started in about the 1930s in which General Motors, Firestone Rubber Phillips Petrollium, Mack Truck and others to form National City Lines to motorize in over 100 citys nation wide, with back room type dealing to scrap all electric properties and promising not to return to pure electric transporatation. As new and more reliable information is developed, solutions to our problems will become clearer. But in the case for pure clean electric mass transit is stronger than ever today-- regardless of the energy crisis. With on-vehicle fossil fuel running we may (only"may") be saving fuel and money, but at the price of our health and very lives being choked off by air and noise pollution. Pure electric mass transit is the only sure answer for a cleaner , healthier environment.

No matter how the efficiency argument comes out, our lives are on the line. I simply must as the slogan has it, "TRAVEL UNDER WIRE,NOT WITH FIRE" in my further opinion , any mass transit agency that does not advocate installing pure electric mass transit systems, and above all does not listen to the demands of the riding public, has what I would call " A public be damed attitude" Sound familiar? At my company we are all orientated to have a customer first attitude. I enjoy that attitude. It gives me a sense of complete satisfaction for my work.

While it may seem wasteful to run long trains at the off peak, there are a number of good reasons to do so. First, it provides for random surges which would overwhelm the bus.

Second, while in the North American context running in the peak period with fifty percent standees, in the off peak providing 2 seats per person makes the vehicle desirable for many and allows for people with packages, etc. to be more comfortable.

Third, there is a cost to reconfiguration in terms of labor and added complexity of operation.

Having ridden the Los Angeles Harbor Freeway Busway, the Los Angeles El Monte Busway, the Cleveland Healthline, the Miami, Florida busway, all of the Pittsburgh busway system, the Ottawa, Canada system, the Halifax, Nova Scotia Link and other "quality" bus operations, as well as light rail in most North American cities, I find the ride better on light rail even when the bus right of way is maintained to the same standard as decent light rail. Because the cars can be longer, they can carry more people per vehicle with more room. Low floor light rail loses less space per vehicle due to wheel intrusion than does the comparable bus. The Cleveland Healthline BRT articulated bus seats only 39 people in a sixty foot articulated bus. Bus does not lend itself to collector, trunk type operation while light rail with bus feeder does.

A mile of double track costs the same as a mile of exclusive two lane busway. The station cost is about the same if you allow for more than one bus at a station. Busways with grade crossings such as the Los Angeles Orange Line and the Miami Busway paralleling US 1 are slower and less safe than comparable light rail lines. Ride them and see. In Los Angeles you can then ride the Blue and Gold lines to compare.

While a bus has better adhesion (and uses more energy because of it) and stopping power in dry weather, it has less adhesion and stopping power in rain and snow. Articulated buses don't do well in snow and ice. Check the web for pictures of Ottawa, Canada and London England buses fouled up by the snow.

There are enough bus rapid transit, street running enhanced bus, light rail and streetcar systems in North America that you can ride so you can make up your own mind as to whether bus is as good as rail.

Posted by: Clark Morris on 6 Feb 09

Ride Los Angeles' Orange Line RBL every work day. It is awful, a true soul deadening experience. Open three years, this is the third time the road surface has had to be totally rebuilt. Which sends the large buses onto city streets and kills rapid travel. The line is at or near capacity, maybe over, different stories in the news.

At rush hours, the buses are filled to overflowing. And the air conditioning breaks down, in 107' heat, never happens on the light rail. One driver told me that they can carry up to 250 people packed in like sardines. Some buses have literally fallen apart in service. The system constantly ends up with long gaps in service at rush hour caused by who knows what. At least once a week, I arrive at 7:15 and no bus until 8:00. There are times when all the buses are traveling in one direction which messes everything up: have waited at North Hollywood at rush hour for up to 30 minutes for a bus. When one finally pulls in, and the driver takes his break, there have been up to 1,000 people waiting to go west. Having Express Buses has not dawned on the management. Each one makes every stop.

One major problem with the buses is bicycles. In LA's mild climate, lots of people bike to the station, take their bike on the bus, and bike to work. Each bus holds a maximum of 3 spots for bikes, on a frame that sticks out from the front. Bike riders may have to wait an hour before a spot is available. Each light rail train car can easily hold 12 bikes.

I ride a RBL every day. It really sucks, absolutely dreadful idea.

Posted by: dalea on 6 Feb 09

Eric L said: "So if electricity is cheap, no one bothers to incur the labor cost of reconfiguring trains for off-peak hours -- you run the same long trains you run in rush hour and people just get lots of space."

Eric, I'm not sure what system you're watching and/or talking about, but most light rail systems do drop cars during off peak hours. Heavy rail and commuter rail systems are far less likely to do so, because as you say, it is some what labor intensive task.

But with most modern light rail systems, the train's operator need do nothing more than pull up on a track where they can drop a car, hit a few buttons, and be on their way without the extra car(s). Not including perhaps pulling into a yard track to uncouple, an operator can drop a car in about 2 to 3 minutes if that.

Posted by: Alan B on 8 Feb 09

The opening to the article is really disingenuous:
"What's the smarter solution for bringing mobility to 21st century cities: bus rapid transit (BRT) or light rail? With questions this big, it's important to consider all the perspectives."

This is not the question addressed by the research which was only a comparison in one corridor. It is not relevant for any other corridor which needs to be examined independently to determine what is the best solution.

Please stay away from such misleading statements. They are not helpful in the least.

George Monbiot wrote a strong piece promoting coaches back in 2006 (based on a scenario proposed by an economist called Alan Storkey).http://www.guardian.co.uk/commentisfree/2006/dec/05/comment.politics
Storkey's idea was to move coach stations out of city centres to the junctions of freeways, where fleets of small vans or jitneys would ferry passengers in and out of the city. This is indeed the lightest intercity transport solution because it uses existing infra. But it will only work if the frequency of coaches is very high - Monbiot talks about every 5-7 minutes on arterial routes.

Just a minor thought. A couple of above comments talk of electric LRT and internal-combustion BRT in an either-or manner. What about electric BRT? Rubber-tired vehicles with pantographs. Trolleybuses with boarding platforms, off-bus ticketing, and all those BRT treatments. No digging up pavement to install rails, just regular paving. Permanent infrastructure overhead to give physical evidence that transit exist on the street and is there to stay. Sure, overhead wires are not all that popular, but it can't be said that BRT cannot be electric, too.

Does anyone know of a city that has tried creating bus-only (or bus-and-bike only) lanes on pairs of appropriate one-way streets? Just as an experiment? My guess is that buses would suddenly run on time, and therefore a lot of people would suddenly want to take buses, which would diminish the traffic in the car lanes and things would work better. If so, the true cost effectiveness of public transport would become obvious even to the most antediluvian of the city fathers. THEN you could decide, should the lanes use buses or light rail.

My own city, Baltimore, MD, is cutting BACK on public transport, right now as we argue, on the grounds that it must "pay for itself," meaning out of current revenues. Is that the hidden assumption in many of these discussions?

Because that's not what planners assume in Europe, where cities work. Or at least that's true as of 20-some years ago, when I interviewed a French city planner who told me that Paris has nine times more people per square mile than New York city. The difference is, Parisians do not need cars: They can count on the Metro. Paris spent (then) a third of its money maintaining and expanding the Metro, because, as the guy said, "If people can't get to work and children can't get to school, you don't have a workable city." Amen, brother.

Posted by: Elise Hancock on 9 Feb 09

Does anyone know of a city that has tried creating bus-only (or bus-and-bike only) lanes on pairs of appropriate one-way streets? Just as an experiment? My guess is that buses would suddenly run on time, and therefore a lot of people would suddenly want to take buses, which would diminish the traffic in the car lanes and things would work better. If so, the true cost effectiveness of public transport would become obvious even to the most antediluvian of the city fathers. THEN you could decide, should the lanes use buses or light rail.

My own city, Baltimore, MD, is cutting BACK on public transport, right now as we argue, on the grounds that it must "pay for itself," meaning out of current revenues. Is that the hidden assumption in many of these discussions?

Because that's not what planners assume in Europe, where cities work. Or at least that's true as of 20-some years ago, when I interviewed a French city planner who told me that Paris has nine times more people per square mile than New York city. The difference is, Parisians do not need cars: They can count on the Metro. Paris spent (then) a third of its money maintaining and expanding the Metro, because, as the guy said, "If people can't get to work and children can't get to school, you don't have a workable city." Amen, brother.

Posted by: Elise Hancock on 9 Feb 09

Answering an above question: Yes there are successful BRT systems. One example is in the brasilian city of Curitiba. The system there works for several years and seems to be working well. The technical people there have been offering their help and experience to cities that want to know it better. Search youtube for "Jaime Lerner" (it was the local mayor behind the system).
I also think that trolley can be a good way to have electrical buses, in Europe we have lots of cities that use trolley bus. It's more flexible than Light rail in cities with steep topography (not all cities are built in plains!) :-)

Posted by: Victor on 9 Feb 09

Did study account for full costs of roadway acquisition and construction beyond present lane and alignment configurations? These capital costs are not trivial.

Posted by: Edicito on 9 Feb 09

While coal and petrol may have comparable environmental effects, one is locally abundant and the other requires subsidy of repressive regimes in Venuzuala, Nigeria and the Middle East. Overhead wires are the best solution. And if the TOD density is even 20% more with rail it is worth it. This must be studied further.

I'm not aware of any city in the US that has tried specifically what you're asking, that being running a bus only (no cars) in one direction on one street, and then using a parallel street to run the bus only in the opposite direction. Not saying that there isn't such an example, just not aware of any.

There is one IMHO successful BRT route in the US, and a few other's that are doing ok, but I would not deem successful. The one successful route is LA's Orange line. However, the Orange line is a victim of its own success.

It has reached its maximum capacity. It can't carry any more passengers at its present service levels, and those levels cannot be increased without serious impact on the local roads that cross the BRT lanes. This is resulting in passengers often needing to watch 2 or 3 full buses go by, before one comes along with enough room for them to board.

LA is currently evaluating its options at this point. One option includes closing the streets that cross the BRT route by building bridges or tunnels or outright closure. A second being looked at is building a subway to replace the BRT.

The third option and serious option, being considered, is how to convert the BRT to Light Rail without actually shutting down the buses in the interim.

After spending millions on BRT, LA is now considering doing what it should have done in the first place, install light rail!

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